Publications

Displaying 301 - 337 of 337
  • Swaab, T. Y., Brown, C. M., & Hagoort, P. (1998). Understanding ambiguous words in sentence contexts: Electrophysiological evidence for delayed contextual selection in Broca's aphasia. Neuropsychologia, 36(8), 737-761. doi:10.1016/S0028-3932(97)00174-7.

    Abstract

    This study investigates whether spoken sentence comprehension deficits in Broca's aphasics results from their inability to access the subordinate meaning of ambiguous words (e.g. bank), or alternatively, from a delay in their selection of the contextually appropriate meaning. Twelve Broca's aphasics and twelve elderly controls were presented with lexical ambiguities in three context conditions, each followed by the same target words. In the concordant condition, the sentence context biased the meaning of the sentence final ambiguous word that was related to the target. In the discordant condition, the sentence context biased the meaning of the sentence final ambiguous word that was incompatible with the target.In the unrelated condition, the sentence-final word was unambiguous and unrelated to the target. The task of the subjects was to listen attentively to the stimuli The activational status of the ambiguous sentence-final words was inferred from the amplitude of the N399 to the targets at two inter-stimulus intervals (ISIs) (100 ms and 1250 ms). At the short ISI, the Broca's aphasics showed clear evidence of activation of the subordinate meaning. In contrast to elderly controls, however, the Broca's aphasics were not successful at selecting the appropriate meaning of the ambiguity in the short ISI version of the experiment. But at the long ISI, in accordance with the performance of the elderly controls, the patients were able to successfully complete the contextual selection process. These results indicate that Broca's aphasics are delayed in the process of contextual selection. It is argued that this finding of delayed selection is compatible with the idea that comprehension deficits in Broca's aphasia result from a delay in the process of integrating lexical information.
  • Swift, M. (1998). [Book review of LOUIS-JACQUES DORAIS, La parole inuit: Langue, culture et société dans l'Arctique nord-américain]. Language in Society, 27, 273-276. doi:10.1017/S0047404598282042.

    Abstract

    This volume on Inuit speech follows the evolution of a native language of the North American Arctic, from its historical roots to its present-day linguistic structure and patterns of use from Alaska to Greenland. Drawing on a wide range of research from the fields of linguistics, anthropology, and sociology, Dorais integrates these diverse perspectives in a comprehensive view of native language development, maintenance, and use under conditions of marginalization due to social transition.
  • Swingley, D. (2005). Statistical clustering and the contents of the infant vocabulary. Cognitive Psychology, 50(1), 86-132. doi:10.1016/j.cogpsych.2004.06.001.

    Abstract

    Infants parse speech into word-sized units according to biases that develop in the first year. One bias, present before the age of 7 months, is to cluster syllables that tend to co-occur. The present computational research demonstrates that this statistical clustering bias could lead to the extraction of speech sequences that are actual words, rather than missegmentations. In English and Dutch, these word-forms exhibit the strong–weak (trochaic) pattern that guides lexical segmentation after 8 months, suggesting that the trochaic parsing bias is learned as a generalization from statistically extracted bisyllables, and not via attention to short utterances or to high-frequency bisyllables. Extracted word-forms come from various syntactic classes, and exhibit distributional characteristics enabling rudimentary sorting of words into syntactic categories. The results highlight the importance of infants’ first year in language learning: though they may know the meanings of very few words, infants are well on their way to building a vocabulary.
  • Swingley, D. (2005). 11-month-olds' knowledge of how familiar words sounds. Developmental Science, 8(5), 432-443. doi:10.1111/j.1467-7687.2005.00432.

    Abstract

    During the first year of life, infants' perception of speech becomes tuned to the phonology of the native language, as revealed in laboratory discrimination and categorization tasks using syllable stimuli. However, the implications of these results for the development of the early vocabulary remain controversial, with some results suggesting that infants retain only vague, sketchy phonological representations of words. Five experiments using a preferential listening procedure tested Dutch 11-month-olds' responses to word, nonword and mispronounced-word stimuli. Infants listened longer to words than nonwords, but did not exhibit this response when words were mispronounced at onset or at offset. In addition, infants preferred correct pronunciations to onset mispronunciations. The results suggest that infants' encoding of familiar words includes substantial phonological detail.
  • ten Bosch, L., & Scharenborg, O. (2005). ASR decoding in a computational model of human word recognition. In Interspeech'2005 - Eurospeech, 9th European Conference on Speech Communication and Technology (pp. 1241-1244). ISCA Archive.

    Abstract

    This paper investigates the interaction between acoustic scores and symbolic mismatch penalties in multi-pass speech decoding techniques that are based on the creation of a segment graph followed by a lexical search. The interaction between acoustic and symbolic mismatches determines to a large extent the structure of the search space of these multipass approaches. The background of this study is a recently developed computational model of human word recognition, called SpeM. SpeM is able to simulate human word recognition data and is built as a multi-pass speech decoder. Here, we focus on unravelling the structure of the search space that is used in SpeM and similar decoding strategies. Finally, we elaborate on the close relation between distances in this search space, and distance measures in search spaces that are based on a combination of acoustic and phonetic features.
  • Terrill, A. (1998). Biri. München: Lincom Europa.

    Abstract

    This work presents a salvage grammar of the Biri language of Eastern Central Queensland, a Pama-Nyungan language belonging to the large Maric subgroup. As the language is no longer used, the grammatical description is based on old written sources and on recordings made by linguists in the 1960s and 1970s. Biri is in many ways typical of the Pama-Nyungan languages of Southern Queensland. It has split case marking systems, marking nouns according to an ergative/absolutive system and pronouns according to a nominative/accusative system. Unusually for its area, Biri also has bound pronouns on its verb, cross-referencing the person, number and case of core participants. As far as it is possible, the grammatical discussion is ‘theory neutral’. The first four chapters deal with the phonology, morphology, and syntax of the language. The last two chapters contain a substantial discussion of Biri’s place in the Pama-Nyungan family. In chapter 6 the numerous dialects of the Biri language are discussed. In chapter 7 the close linguistic relationship between Biri and the surrounding languages is examined.
  • Theakston, A. L., Lieven, E. V., Pine, J. M., & Rowland, C. F. (2005). The acquisition of auxiliary syntax: BE and HAVE. Cognitive Linguistics, 16(1), 247-277. doi:10.1515/cogl.2005.16.1.247.

    Abstract

    This study examined patterns of auxiliary provision and omission for the auxiliaries BE and HAVE in a longitudinal data set from 11 children between the ages of two and three years. Four possible explanations for auxiliary omission—a lack of lexical knowledge, performance limitations in production, the Optional Infinitive hypothesis, and patterns of auxiliary use in the input—were examined. The data suggest that although none of these accounts provides a full explanation for the pattern of auxiliary use and nonuse observed in children's early speech, integrating input-based and lexical learning-based accounts of early language acquisition within a constructivist approach appears to provide a possible framework in which to understand the patterns of auxiliary use found in the children's speech. The implications of these findings for models of children's early language acquisition are discussed.
  • Trilsbeek, P., & Wittenburg, P. (2005). Archiving challenges. In J. Gippert, N. Himmelmann, & U. Mosel (Eds.), Essentials of language documentation (pp. 311-335). Berlin: Mouton de Gruyter.
  • Van Turennout, M., Hagoort, P., & Brown, C. M. (1998). Brain activitity during speaking: From syntax to phonology in 40 milliseconds. Science, 280, 572-574.

    Abstract

    In normal conversation, speakers translate thoughts into words at high speed. To enable this speed, the retrieval of distinct types of linguistic knowledge has to be orchestrated with millisecond precision. The nature of this orchestration is still largely unknown. This report presents dynamic measures of the real-time activation of two basic types of linguistic knowledge, syntax and phonology. Electrophysiological data demonstrate that during noun-phrase production speakers retrieve the syntactic gender of a noun before its abstract phonological properties. This two-step process operates at high speed: the data show that phonological information is already available 40 milliseconds after syntactic properties have been retrieved.
  • Van Turennout, M., Hagoort, P., & Brown, C. M. (1998). Brain activity during speaking: From syntax to phonology in 40 milliseconds. Science, 280(5363), 572-574. doi:10.1126/science.280.5363.572.
  • Van de Geer, J. P., & Levelt, W. J. M. (1963). Detection of visual patterns disturbed by noise: An exploratory study. Quarterly Journal of Experimental Psychology, 15, 192-204. doi:10.1080/17470216308416324.

    Abstract

    An introductory study of the perception of stochastically specified events is reported. The initial problem was to determine whether the perceiver can split visual input data of this kind into random and determined components. The inability of subjects to do so with the stimulus material used (a filmlike sequence of dot patterns), led to the more general question of how subjects code this kind of visual material. To meet the difficulty of defining the subjects' responses, two experiments were designed. In both, patterns were presented as a rapid sequence of dots on a screen. The patterns were more or less disturbed by “noise,” i.e. the dots did not appear exactly at their proper places. In the first experiment the response was a rating on a semantic scale, in the second an identification from among a set of alternative patterns. The results of these experiments give some insight in the coding systems adopted by the subjects. First, noise appears to be detrimental to pattern recognition, especially to patterns with little spread. Second, this shows connections with the factors obtained from analysis of the semantic ratings, e.g. easily disturbed patterns show a large drop in the semantic regularity factor, when only a little noise is added.
  • Van Donselaar, W., Koster, M., & Cutler, A. (2005). Exploring the role of lexical stress in lexical recognition. Quarterly Journal of Experimental Psychology, 58A(2), 251-273. doi:10.1080/02724980343000927.

    Abstract

    Three cross-modal priming experiments examined the role of suprasegmental information in the processing of spoken words. All primes consisted of truncated spoken Dutch words. Recognition of visually presented word targets was facilitated by prior auditory presentation of the first two syllables of the same words as primes, but only if they were appropriately stressed (e.g., OKTOBER preceded by okTO-); inappropriate stress, compatible with another word (e.g., OKTOBER preceded by OCto-, the beginning of octopus), produced inhibition. Monosyllabic fragments (e.g., OC-) also produced facilitation when appropriately stressed; if inappropriately stressed, they produced neither facilitation nor inhibition. The bisyllabic fragments that were compatible with only one word produced facilitation to semantically associated words, but inappropriate stress caused no inhibition of associates. The results are explained within a model of spoken-word recognition involving competition between simultaneously activated phonological representations followed by activation of separate conceptual representations for strongly supported lexical candidates; at the level of the phonological representations, activation is modulated by both segmental and suprasegmental information.
  • Van Berkum, J. J. A., Brown, C. M., Zwitserlood, P., Kooijman, V., & Hagoort, P. (2005). Anticipating upcoming words in discourse: Evidence from ERPs and reading times. Journal of Experimental Psychology: Learning, Memory, and Cognition, 31(3), 443-467. doi:10.1037/0278-7393.31.3.443.

    Abstract

    The authors examined whether people can use their knowledge of the wider discourse rapidly enough to anticipate specific upcoming words as a sentence is unfolding. In an event-related brain potential (ERP) experiment, subjects heard Dutch stories that supported the prediction of a specific noun. To probe whether this noun was anticipated at a preceding indefinite article, stories were continued with a gender-marked adjective whose suffix mismatched the upcoming noun's syntactic gender. Prediction-inconsistent adjectives elicited a differential ERP effect, which disappeared in a no-discourse control experiment. Furthermore, in self-paced reading, prediction-inconsistent adjectives slowed readers down before the noun. These findings suggest that people can indeed predict upcoming words in fluent discourse and, moreover, that these predicted words can immediately begin to participate in incremental parsing operations.
  • Van Halteren, H., Baayen, R. H., Tweedie, F., Haverkort, M., & Neijt, A. (2005). New machine learning methods demonstrate the existence of a human stylome. Journal of Quantitative Linguistics, 12(1), 65-77. doi:10.1080/09296170500055350.

    Abstract

    Earlier research has shown that established authors can be distinguished by measuring specific properties of their writings, their stylome as it were. Here, we examine writings of less experienced authors. We succeed in distinguishing between these authors with a very high probability, which implies that a stylome exists even in the general population. However, the number of traits needed for so successful a distinction is an order of magnitude larger than assumed so far. Furthermore, traits referring to syntactic patterns prove less distinctive than traits referring to vocabulary, but much more distinctive than expected on the basis of current generativist theories of language learning.
  • Van Valin Jr., R. D. (2005). Exploring the syntax-semantics interface. Cambridge University Press.

    Abstract

    Language is a system of communication in which grammatical structures function to express meaning in context. While all languages can achieve the same basic communicative ends, they each use different means to achieve them, particularly in the divergent ways that syntax, semantics and pragmatics interact across languages. This book looks in detail at how structure, meaning, and communicative function interact in human languages. Working within the framework of Role and Reference Grammar (RRG), Van Valin proposes a set of rules, called the ‘linking algorithm’, which relates syntactic and semantic representations to each other, with discourse-pragmatics playing a role in the linking. Using this model, he discusses the full range of grammatical phenomena, including the structures of simple and complex sentences, verb and argument structure, voice, reflexivization and extraction restrictions. Clearly written and comprehensive, this book will be welcomed by all those working on the interface between syntax, semantics and pragmatics.
  • Van Geenhoven, V. (1998). On the Argument Structure of some Noun Incorporating Verbs in West Greenlandic. In M. Butt, & W. Geuder (Eds.), The Projection of Arguments - Lexical and Compositional Factors (pp. 225-263). Stanford, CA, USA: CSLI Publications.
  • Van Valin Jr., R. D. (1998). The acquisition of WH-questions and the mechanisms of language acquisition. In M. Tomasello (Ed.), The new psychology of language: Cognitive and functional approaches to language structure (pp. 221-249). Mahwah, New Jersey: Erlbaum.
  • Van de Geer, J. P., Levelt, W. J. M., & Plomp, R. (1962). The connotation of musical consonance. Acta Psychologica, 20, 308-319.

    Abstract

    As a preliminary to further research on musical consonance an explanatory investigation was made on the different modes of judgment of musical intervals. This was done by way of a semantic differential. Subjects rated 23 intervals against 10 scales. In a factor analysis three factors appeared: pitch, evaluation and fusion. The relation between these factors and some physical characteristics has been investigated. The scale consonant-dissonant showed to be purely evaluative (in opposition to Stumpf's theory). This evaluative connotation is not in accordance with the musicological meaning of consonance. Suggestions to account for this difference have been given.
  • Verhagen, J. (2005). The role of the nonmodal auxiliary 'hebben' in Dutch as a second language. Zeitschrift für Literaturwissenschaft und Linguistik, 140, 109-127.

    Abstract

    The acquisition of non-modal auxiliaries has been assumed to constitute an important step in the acquisition of finiteness in Germanic languages (cf. Jordens/Dimroth 2005, Jordens 2004, Becker 2005). This paper focuses onthe role of the auxiliary hebben (>to have<) in the acquisition of Dutch as a second language. More specifically, it investigates whether learners' production of hebben is related to their acquisition of two phenomena commonly associated with finiteness, i.e., topicalization and negation. Data are presented from 16 Turkish and 36 Moroccan learners of Dutch who participated in an experiment involving production and imitation tasks. The production data suggest that learners use topicalization and post-verbal negation only after they have learned to produce the auxiliary hebben. The results from the imitation task indicate, that learners are more sensitive to topicalization and post-verbal negation in sentences with hebben than in sentences with lexical verbs. Interestingly this holds also for learners that did not show productive command of hebben in the production tasks. Thus, in general, the results of the experiment provide support for the idea that non-modal auxiliaries are crucial in the acquisition of (certain properties of) finiteness.
  • Verhagen, J. (2005). The role of the nonmodal auxiliary 'hebben' in Dutch as a second language. Toegepaste Taalwetenschap in Artikelen, 73, 41-52.
  • De Vos, C. (2005). Cataphoric pronoun resolution (Unpublished bachelor thesis). Nijmegen: Department of Linguistics, Radboud University.

    Abstract

    Processing of cataphoric coreferential relationships.
  • Warner, N., Smits, R., McQueen, J. M., & Cutler, A. (2005). Phonological and statistical effects on timing of speech perception: Insights from a database of Dutch diphone perception. Speech Communication, 46(1), 53-72. doi:10.1016/j.specom.2005.01.003.

    Abstract

    We report detailed analyses of a very large database on timing of speech perception collected by Smits et al. (Smits, R., Warner, N., McQueen, J.M., Cutler, A., 2003. Unfolding of phonetic information over time: A database of Dutch diphone perception. J. Acoust. Soc. Am. 113, 563–574). Eighteen listeners heard all possible diphones of Dutch, gated in portions of varying size and presented without background noise. The present report analyzes listeners’ responses across gates in terms of phonological features (voicing, place, and manner for consonants; height, backness, and length for vowels). The resulting patterns for feature perception differ from patterns reported when speech is presented in noise. The data are also analyzed for effects of stress and of phonological context (neighboring vowel vs. consonant); effects of these factors are observed to be surprisingly limited. Finally, statistical effects, such as overall phoneme frequency and transitional probabilities, along with response biases, are examined; these too exercise only limited effects on response patterns. The results suggest highly accurate speech perception on the basis of acoustic information alone.
  • Warner, N., Kim, J., Davis, C., & Cutler, A. (2005). Use of complex phonological patterns in speech processing: Evidence from Korean. Journal of Linguistics, 41(2), 353-387. doi:10.1017/S0022226705003294.

    Abstract

    Korean has a very complex phonology, with many interacting alternations. In a coronal-/i/ sequence, depending on the type of phonological boundary present, alternations such as palatalization, nasal insertion, nasal assimilation, coda neutralization, and intervocalic voicing can apply. This paper investigates how the phonological patterns of Korean affect processing of morphemes and words. Past research on languages such as English, German, Dutch, and Finnish has shown that listeners exploit syllable structure constraints in processing speech and segmenting it into words. The current study shows that in parsing speech, listeners also use much more complex patterns that relate the surface phonological string to various boundaries.
  • Wassenaar, M., & Hagoort, P. (2005). Word-category violations in patients with Broca's aphasia: An ERP study. Brain and Language, 92, 117-137. doi:10.1016/j.bandl.2004.05.011.

    Abstract

    An event-related brain potential experiment was carried out to investigate on-line syntactic processing in patients with Broca’s aphasia. Subjects were visually presented with sentences that were either syntactically correct or contained violations of word-category. Three groups of subjects were tested: Broca patients (N=11), non-aphasic patients with a right hemisphere (RH) lesion (N=9), and healthy aged-matched controls (N=15). Both control groups appeared sensitive to the violations of word-category as shown by clear P600/SPS effects. The Broca patients displayed only a very reduced and delayed P600/SPS effect. The results are discussed in the context of a lexicalist parsing model. It is concluded that Broca patients are hindered to detect on-line violations of word-category, if word class information is incomplete or delayed available.
  • Wassenaar, M. (2005). Agrammatic comprehension: An electrophysiological approach. PhD Thesis, Radboud University Nijmegen, Nijmegen. doi:10.17617/2.60340.

    Abstract

    This dissertation focuses on syntactic comprehension problems in patients with Broca's aphasia from an electrophysiological perspective. The central objective of this dissertation was to further explore what syntax-related event-related brain potential (ERP) effects can reveal about the nature of the deficit that underlies syntactic comprehension problems in patients with Broca's aphasia. Chapter two to four describe experiments in which event-related brain potentials were recorded while subjects (Broca patients, non-aphasic patients with a right-hemisphere lesion, and healthy elderly controls) were presented with sentences that contained either violations of syntactic constraints or were syntactically correct. Chapter two investigates ERP effects of subject-verb agreement violations in the different subject groups, and seeks to answer the following questions: Do agrammatic comprehenders show sensitivity to subject-verb agreement violations as indicated by a syntax-related ERP effect? In addition, does the severity of the syntactic comprehension impairment in the Broca patients affect the ERP responses? Chapter three describes an investigation of whether Broca patients show sensitivity to violations of word order as indicated by a syntax-related ERP effect, and whether the ERP responses in the Broca patients are affected by the severity of their syntactic comprehension impairment. Chapter four reports on ERP effects of violations of word-category. In addition, also a semantic violation condition was added to track possible dissociations in the sensitivity to semantic and syntactic information in the Broca patients. Chapter five describes the development of a paradigm in which the electrophysiological approach and the classical sentence-picture matching approach are combined. In this chapter, the ERP method is applied to study on-line thematic role assignment in Broca patients during sentence-picture matching. Also the relation between ERP effects and behavioral responses is pursued. Finally, Chapter 6 provides a summary of the main findings of the experiments and a general discussion.

    Additional information

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  • Weber, A. (1998). Listening to nonnative language which violates native assimilation rules. In D. Duez (Ed.), Proceedings of the European Scientific Communication Association workshop: Sound patterns of Spontaneous Speech (pp. 101-104).

    Abstract

    Recent studies using phoneme detection tasks have shown that spoken-language processing is neither facilitated nor interfered with by optional assimilation, but is inhibited by violation of obligatory assimilation. Interpretation of these results depends on an assessment of their generality, specifically, whether they also obtain when listeners are processing nonnative language. Two separate experiments are presented in which native listeners of German and native listeners of Dutch had to detect a target fricative in legal monosyllabic Dutch nonwords. All of the nonwords were correct realisations in standard Dutch. For German listeners, however, half of the nonwords contained phoneme strings which violate the German fricative assimilation rule. Whereas the Dutch listeners showed no significant effects, German listeners detected the target fricative faster when the German fricative assimilation was violated than when no violation occurred. The results might suggest that violation of assimilation rules does not have to make processing more difficult per se.
  • Wegener, C. (2005). Major word classes in Savosavo. Grazer Linguistische Studien, 64, 29-52.
  • Wittek, A. (1998). Learning verb meaning via adverbial modification: Change-of-state verbs in German and the adverb "wieder" again. In A. Greenhill, M. Hughes, H. Littlefield, & H. Walsh (Eds.), Proceedings of the 22nd Annual Boston University Conference on Language Development (pp. 779-790). Somerville, MA: Cascadilla Press.
  • Wittenburg, P., Skiba, R., & Trilsbeek, P. (2005). The language archive at the MPI: Contents, tools, and technologies. Language Archives Newsletter, 5, 7-9.
  • Wohlgemuth, J., & Dirksmeyer, T. (Eds.). (2005). Bedrohte Vielfalt. Aspekte des Sprach(en)tods – Aspects of language death. Berlin: Weißensee.

    Abstract

    About 5,000 languages are spoken in the world today. More than half of them have less than 10,000 speakers, a quarter of them even fewer than 1,000. The majority of these “small” languages will not live to see the end of this century; some estimates predict that no more than a dozen languages will still be spoken by the turn of the next millennium. This collection of papers approaches the subject of language extinction through five major topics: general aspects of language death, case studies, endangered subsystems, language protection and revitalization, language ecology. In 24 articles, the authors address the causes, manifestations, and consequences of language endangerment and extinction as well as the linguistic and social changes associated with it, drawing examples from a large number of languages.
  • Zeshan, U. (2005). Sign languages. In M. Haspelmath, M. S. Dryer, D. Gil, & B. Comrie (Eds.), The world atlas of language structures (pp. 558-559). Oxford: Oxford University Press.
  • Zeshan, U. (2005). Question particles in sign languages. In M. Haspelmath, M. S. Dryer, D. Gil, & B. Comrie (Eds.), The world atlas of language structures (pp. 564-567). Oxford: Oxford University Press.
  • Zeshan, U., & Panda, S. (2005). Professional course in Indian sign language. Mumbai: Ali Yavar Jung National Institute for the Hearing Handicapped.
  • Zeshan, U., Pfau, R., & Aboh, E. (2005). When a wh-word is not a wh-word: the case of Indian sign language. In B. Tanmoy (Ed.), Yearbook of South Asian languages and linguistics 2005 (pp. 11-43). Berlin: Mouton de Gruyter.
  • Zeshan, U., Vasishta, M. N., & Sethna, M. (2005). Implementation of Indian Sign Language in educational settings. Asia Pacific Disability Rehabilitation Journal, 16(1), 16-40.

    Abstract

    This article reports on several sub-projects of research and development related to the use of Indian Sign Language in educational settings. In many countries around the world, sign languages are now recognised as the legitimate, full-fledged languages of the deaf communities that use them. In India, the development of sign language resources and their application in educational contexts, is still in its initial stages. The work reported on here, is the first principled and comprehensive effort of establishing educational programmes in Indian Sign Language at a national level. Programmes are of several types: a) Indian Sign Language instruction for hearing people; b) sign language teacher training programmes for deaf people; and c) educational materials for use in schools for the Deaf. The conceptual approach used in the programmes for deaf students is known as bilingual education, which emphasises the acquisition of a first language, Indian Sign Language, alongside the acquisition of spoken languages, primarily in their written form.
  • Zeshan, U. (2005). Irregular negatives in sign languages. In M. Haspelmath, M. S. Dryer, D. Gil, & B. Comrie (Eds.), The world atlas of language structures (pp. 560-563). Oxford: Oxford University Press.
  • Zhang, J., Bao, S., Furumai, R., Kucera, K. S., Ali, A., Dean, N. M., & Wang, X.-F. (2005). Protein phosphatase 5 is required for ATR-mediated checkpoint activation. Molecular and Cellular Biology, 25, 9910-9919. doi:10.1128/​MCB.25.22.9910-9919.2005.

    Abstract

    In response to DNA damage or replication stress, the protein kinase ATR is activated and subsequently transduces genotoxic signals to cell cycle control and DNA repair machinery through phosphorylation of a number of downstream substrates. Very little is known about the molecular mechanism by which ATR is activated in response to genotoxic insults. In this report, we demonstrate that protein phosphatase 5 (PP5) is required for the ATR-mediated checkpoint activation. PP5 forms a complex with ATR in a genotoxic stress-inducible manner. Interference with the expression or the activity of PP5 leads to impairment of the ATR-mediated phosphorylation of hRad17 and Chk1 after UV or hydroxyurea treatment. Similar results are obtained in ATM-deficient cells, suggesting that the observed defect in checkpoint signaling is the consequence of impaired functional interaction between ATR and PP5. In cells exposed to UV irradiation, PP5 is required to elicit an appropriate S-phase checkpoint response. In addition, loss of PP5 leads to premature mitosis after hydroxyurea treatment. Interestingly, reduced PP5 activity exerts differential effects on the formation of intranuclear foci by ATR and replication protein A, implicating a functional role for PP5 in a specific stage of the checkpoint signaling pathway. Taken together, our results suggest that PP5 plays a critical role in the ATR-mediated checkpoint activation.

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